Help needed to recover a RAID5 btrfs

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* Help needed to recover a RAID5 btrfs
@ 2015-05-25 16:06 Felix Koop
  2015-05-26  5:38 ` Duncan
                   ` (2 more replies)
  0 siblings, 3 replies; 6+ messages in thread
From: Felix Koop @ 2015-05-25 16:06 UTC (permalink / raw)
  To: linux-btrfs

Hello,

I have a RAID5 filesystem where one disk has crashed. Now the filesystem is not
recognized any more. Any help available?

Here is some info:

root@server:~# uname -a
Linux server 4.0.0-1-amd64 #1 SMP Debian 4.0.2-1 (2015-05-11) x86_64 GNU/Linux

root@server:~# btrfs --version
btrfs-progs v4.0

root@server:~# btrfs f sh /dev/Data1vg/afs0
warning, device 3 is missing
warning devid 3 not found already
checksum verify failed on 1111813750784 found 18019A1D wanted FCE227AB
checksum verify failed on 1111813750784 found 18019A1D wanted FCE227AB
bytenr mismatch, want=1111813750784, have=65536
Couldn't read tree root
Label: none uuid: 7d4b023a-a1ef-4991-b01d-31e7c4fdfbcf
 Total devices 3 FS bytes used 213.96GiB
 devid 2 size 150.00GiB used 108.53GiB path /dev/mapper/Data1vg-afs0
 devid 4 size 150.00GiB used 108.53GiB path /dev/mapper/Data3vg-afs0
 *** Some devices missing

btrfs-progs v4.0

root@server:~# mount -o degraded -r /dev/Data1vg/afs0 /mnt
mount: wrong fs type, bad option, bad superblock on /dev/mapper/Data1vg-afs0,
 missing codepage or helper program, or other error

In some cases useful info is found in syslog – try
 dmesg | tail or so.

root@server:~# dmesg | tail
[104991.996065] BTRFS: open_ctree failed
[105527.836798] blk_update_request: I/O error, dev fd0, sector 0
[105527.839477] floppy: error -5 while reading block 0
[105555.615991] BTRFS info (device dm-52): allowing degraded mounts
[105555.616000] BTRFS info (device dm-52): disk space caching is enabled
[105555.665644] BTRFS: bdev (null) errs: wr 38, rd 0, flush 0, corrupt 0, gen 0
[105556.213570] BTRFS (device dm-52): bad tree block start 14290338419558610620
1111828267008
[105556.216649] BTRFS (device dm-52): bad tree block start 14290338419558610620
1111828267008
[105556.219364] BTRFS: Failed to read block groups: -5
[105556.236056] BTRFS: open_ctree failed


If more info is needed, just tell me what I should do. Thanks.

---

Kind greetings

Felix Koop

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: Help needed to recover a RAID5 btrfs
  2015-05-25 16:06 Help needed to recover a RAID5 btrfs Felix Koop
@ 2015-05-26  5:38 ` Duncan
  2015-05-26  5:56 ` Qu Wenruo
  2015-05-26 22:44 ` Omar Sandoval
  2 siblings, 0 replies; 6+ messages in thread
From: Duncan @ 2015-05-26  5:38 UTC (permalink / raw)
  To: linux-btrfs

Felix Koop posted on Mon, 25 May 2015 18:06:20 +0200 as excerpted:

> I have a RAID5 filesystem where one disk has crashed. Now the filesystem
> is not recognized any more. Any help available?
> 
> Here is some info:
> 
> root@server:~# uname -a Linux server 4.0.0-1-amd64 #1 SMP Debian 4.0.2-1
> (2015-05-11) x86_64 GNU/Linux
> 
> root@server:~# btrfs --version btrfs-progs v4.0

Commendations on at least running current versions.  With code as new as 
btrfs raid56 mode, that's absolutely critical, so I'm glad to see you got 
it covered! =:^)

This isn't going to help with the current problem, but it might be useful 
in general...  Note that I'm just a btrfs user/admin and list regular, 
not a dev, and that my own btrfs use-case is btrfs raid1 mode, so what I 
know about btrfs raid56 mode (covering both raid5 and raid6) is what I've 
found on the wiki and the list.  Disclaimer out of the way...

FWIW, btrfs raid56 mode was only actually theoretically complete with 
kernel 3.19, and is still very new and buggy.

If you're simply testing it, great, we need testers to help it get to 
usability. =:^)

If OTOH you're actually expecting it to work, I'd strongly recommend 
avoiding raid56 mode until it has at /least/ a /couple/ kernel cycles 
under its belt after completion... which would be 4.1 since 3.19 was code-
completion, and preferably something closer to a year, five kernel cycles 
or so, thus 4.4.

In the mean time, for multi-device btrfs modes with raid redundancy, I'd 
recommend sticking with either raid1 or raid10 modes as at this point 
they are both far more mature and tested, basically to the same level of 
maturity btrfs itself is, that being not entirely stable yet, but 
reasonably usable as long as you're following the sysadmins' backups 
rule, that in turn being, if it's not backed up you by definition don't 
care if you lose it, no matter what you claim, with the corollary being 
that a would-be backup isn't a backup, until you've tested that you can 
recover from it.

As for help with your current broken btrfs raid5, I'll refer you to 
others with actual experience with it. =:^/

-- 
Duncan - List replies preferred.   No HTML msgs.
"Every nonfree program has a lord, a master --
and if you use the program, he is your master."  Richard Stallman

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: Help needed to recover a RAID5 btrfs
  2015-05-25 16:06 Help needed to recover a RAID5 btrfs Felix Koop
  2015-05-26  5:38 ` Duncan
@ 2015-05-26  5:56 ` Qu Wenruo
  2015-05-26 20:15   ` Felix Koop
  2015-05-26 22:44 ` Omar Sandoval
  2 siblings, 1 reply; 6+ messages in thread
From: Qu Wenruo @ 2015-05-26  5:56 UTC (permalink / raw)
  To: Felix Koop, linux-btrfs

> Hello,
>
> I have a RAID5 filesystem where one disk has crashed. Now the filesystem is not
> recognized any more. Any help available?
>
> Here is some info:
>
> root@server:~# uname -a
> Linux server 4.0.0-1-amd64 #1 SMP Debian 4.0.2-1 (2015-05-11) x86_64 GNU/Linux
>
> root@server:~# btrfs --version
> btrfs-progs v4.0
>
> root@server:~# btrfs f sh /dev/Data1vg/afs0
> warning, device 3 is missing
> warning devid 3 not found already
> checksum verify failed on 1111813750784 found 18019A1D wanted FCE227AB
> checksum verify failed on 1111813750784 found 18019A1D wanted FCE227AB
> bytenr mismatch, want=1111813750784, have=65536
> Couldn't read tree root
Tree root is corrupted, which is not a good news.

> Label: none uuid: 7d4b023a-a1ef-4991-b01d-31e7c4fdfbcf
>   Total devices 3 FS bytes used 213.96GiB
>   devid 2 size 150.00GiB used 108.53GiB path /dev/mapper/Data1vg-afs0
>   devid 4 size 150.00GiB used 108.53GiB path /dev/mapper/Data3vg-afs0
>   *** Some devices missing
The device 3, I guest it's /dev/mapper/data2vg-afs0, does it still 
exists in /dev/mapper?
>
> btrfs-progs v4.0
>
> root@server:~# mount -o degraded -r /dev/Data1vg/afs0 /mnt
> mount: wrong fs type, bad option, bad superblock on /dev/mapper/Data1vg-afs0,
>   missing codepage or helper program, or other error
>
> In some cases useful info is found in syslog – try
>   dmesg | tail or so.
>
> root@server:~# dmesg | tail
> [104991.996065] BTRFS: open_ctree failed
> [105527.836798] blk_update_request: I/O error, dev fd0, sector 0
> [105527.839477] floppy: error -5 while reading block 0
> [105555.615991] BTRFS info (device dm-52): allowing degraded mounts
> [105555.616000] BTRFS info (device dm-52): disk space caching is enabled
> [105555.665644] BTRFS: bdev (null) errs: wr 38, rd 0, flush 0, corrupt 0, gen 0
> [105556.213570] BTRFS (device dm-52): bad tree block start 14290338419558610620
> 1111828267008
> [105556.216649] BTRFS (device dm-52): bad tree block start 14290338419558610620
> 1111828267008
> [105556.219364] BTRFS: Failed to read block groups: -5
> [105556.236056] BTRFS: open_ctree failed
>
>
> If more info is needed, just tell me what I should do. Thanks.
Need some extra info:
  btrfs-show-super -a -f /dev/mapper/Data1vg-afs0
  btrfs-show-super -a -f /dev/mapper/Data2vg-afs0 (If that is device3 
and exists)
  btrfs-show-super -a -f /dev/mapper/Data3vg-afs0

Maybe we can use old super to restore it to a mountable status.

If you have spare space to backup all the 3 devices, it's recommended to 
do it, as some repair tips may cause some write into disk, and may even 
make things worse.

Thanks,
Qu

>
> ---
>
> Kind greetings
>
> Felix Koop
> --
> To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: Help needed to recover a RAID5 btrfs
  2015-05-26  5:56 ` Qu Wenruo
@ 2015-05-26 20:15   ` Felix Koop
  2015-05-30 12:03     ` Felix Koop
  0 siblings, 1 reply; 6+ messages in thread
From: Felix Koop @ 2015-05-26 20:15 UTC (permalink / raw)
  To: linux-btrfs, Qu Wenruo

> Qu Wenruo <quwenruo@cn.fujitsu.com> hat am 26. Mai 2015 um 07:56 geschrieben:
> 
> > Label: none uuid: 7d4b023a-a1ef-4991-b01d-31e7c4fdfbcf
> >   Total devices 3 FS bytes used 213.96GiB
> >   devid 2 size 150.00GiB used 108.53GiB path /dev/mapper/Data1vg-afs0
> >   devid 4 size 150.00GiB used 108.53GiB path /dev/mapper/Data3vg-afs0
> >   *** Some devices missing
> The device 3, I guest it's /dev/mapper/data2vg-afs0, does it still 
> exists in /dev/mapper?

No, the disk crashed, so that the device does no longer exist.

> Need some extra info:
>   btrfs-show-super -a -f /dev/mapper/Data1vg-afs0

root@server:~# btrfs-show-super -a -f /dev/mapper/Data1vg-afs0
superblock: bytenr=65536, device=/dev/mapper/Data1vg-afs0
---------------------------------------------------------
csum			0xc33db89c [match]
bytenr			65536
flags			0x1
magic			_BHRfS_M [match]
fsid			7d4b023a-a1ef-4991-b01d-31e7c4fdfbcf
label			
generation		35278
root			1111813750784
sys_array_size		161
chunk_root_generation	33824
root_level		1
chunk_root		1111721295872
chunk_root_level	1
log_root		0
log_root_transid	0
log_root_level		0
total_bytes		483183820800
bytes_used		229738524672
sectorsize		4096
nodesize		16384
leafsize		16384
stripesize		4096
root_dir		6
num_devices		3
compat_flags		0x0
compat_ro_flags		0x0
incompat_flags		0xe1
			( MIXED_BACKREF |
			  BIG_METADATA |
			  EXTENDED_IREF |
			  RAID56 )
csum_type		0
csum_size		4
cache_generation	35278
uuid_tree_generation	35278
dev_item.uuid		5e5332c3-9e02-4b86-a84e-709f6ac4196b
dev_item.fsid		7d4b023a-a1ef-4991-b01d-31e7c4fdfbcf [match]
dev_item.type		0
dev_item.total_bytes	161061273600
dev_item.bytes_used	116534542336
dev_item.io_align	4096
dev_item.io_width	4096
dev_item.sector_size	4096
dev_item.devid		2
dev_item.dev_group	0
dev_item.seek_speed	0
dev_item.bandwidth	0
dev_item.generation	0
sys_chunk_array[2048]:
	item 0 key (FIRST_CHUNK_TREE CHUNK_ITEM 1111721246720)
		chunk length 67108864 owner 2 type SYSTEM|RAID5 num_stripes 3
			stripe 0 devid 2 offset 1048576
			stripe 1 devid 4 offset 1048576
			stripe 2 devid 3 offset 1048576
backup_roots[4]:
	backup 0:
		backup_tree_root:	1111813750784	gen: 35278	level: 1
		backup_chunk_root:	1111721295872	gen: 33824	level: 1
		backup_extent_root:	1111813963776	gen: 35278	level: 2
		backup_fs_root:		1111836409856	gen: 35277	level: 2
		backup_dev_root:	1111814504448	gen: 35278	level: 1
		backup_csum_root:	1111814963200	gen: 35278	level: 2
		backup_total_bytes:	483183820800
		backup_bytes_used:	229738524672
		backup_num_devices:	3

	backup 1:
		backup_tree_root:	1111811768320	gen: 35275	level: 1
		backup_chunk_root:	1111721295872	gen: 33824	level: 1
		backup_extent_root:	1111808262144	gen: 35275	level: 2
		backup_fs_root:		1111808081920	gen: 35275	level: 2
		backup_dev_root:	1112427905024	gen: 33824	level: 1
		backup_csum_root:	1111814733824	gen: 35275	level: 2
		backup_total_bytes:	483183820800
		backup_bytes_used:	229738541056
		backup_num_devices:	3

	backup 2:
		backup_tree_root:	1111816585216	gen: 35276	level: 1
		backup_chunk_root:	1111721295872	gen: 33824	level: 1
		backup_extent_root:	1111815340032	gen: 35276	level: 2
		backup_fs_root:		1111808983040	gen: 35277	level: 2
		backup_dev_root:	1112427905024	gen: 33824	level: 1
		backup_csum_root:	1111818010624	gen: 35276	level: 2
		backup_total_bytes:	483183820800
		backup_bytes_used:	229738541056
		backup_num_devices:	3

	backup 3:
		backup_tree_root:	1111842062336	gen: 35277	level: 1
		backup_chunk_root:	1111721295872	gen: 33824	level: 1
		backup_extent_root:	1111825956864	gen: 35277	level: 2
		backup_fs_root:		1111836409856	gen: 35277	level: 2
		backup_dev_root:	1111842095104	gen: 35277	level: 1
		backup_csum_root:	1111842160640	gen: 35277	level: 2
		backup_total_bytes:	483183820800
		backup_bytes_used:	229738524672
		backup_num_devices:	3


superblock: bytenr=67108864, device=/dev/mapper/Data1vg-afs0
---------------------------------------------------------
csum			0x635c9052 [match]
bytenr			67108864
flags			0x1
magic			_BHRfS_M [match]
fsid			7d4b023a-a1ef-4991-b01d-31e7c4fdfbcf
label			
generation		35278
root			1111813750784
sys_array_size		161
chunk_root_generation	33824
root_level		1
chunk_root		1111721295872
chunk_root_level	1
log_root		0
log_root_transid	0
log_root_level		0
total_bytes		483183820800
bytes_used		229738524672
sectorsize		4096
nodesize		16384
leafsize		16384
stripesize		4096
root_dir		6
num_devices		3
compat_flags		0x0
compat_ro_flags		0x0
incompat_flags		0xe1
			( MIXED_BACKREF |
			  BIG_METADATA |
			  EXTENDED_IREF |
			  RAID56 )
csum_type		0
csum_size		4
cache_generation	35278
uuid_tree_generation	35278
dev_item.uuid		5e5332c3-9e02-4b86-a84e-709f6ac4196b
dev_item.fsid		7d4b023a-a1ef-4991-b01d-31e7c4fdfbcf [match]
dev_item.type		0
dev_item.total_bytes	161061273600
dev_item.bytes_used	116534542336
dev_item.io_align	4096
dev_item.io_width	4096
dev_item.sector_size	4096
dev_item.devid		2
dev_item.dev_group	0
dev_item.seek_speed	0
dev_item.bandwidth	0
dev_item.generation	0
sys_chunk_array[2048]:
	item 0 key (FIRST_CHUNK_TREE CHUNK_ITEM 1111721246720)
		chunk length 67108864 owner 2 type SYSTEM|RAID5 num_stripes 3
			stripe 0 devid 2 offset 1048576
			stripe 1 devid 4 offset 1048576
			stripe 2 devid 3 offset 1048576
backup_roots[4]:
	backup 0:
		backup_tree_root:	1111813750784	gen: 35278	level: 1
		backup_chunk_root:	1111721295872	gen: 33824	level: 1
		backup_extent_root:	1111813963776	gen: 35278	level: 2
		backup_fs_root:		1111836409856	gen: 35277	level: 2
		backup_dev_root:	1111814504448	gen: 35278	level: 1
		backup_csum_root:	1111814963200	gen: 35278	level: 2
		backup_total_bytes:	483183820800
		backup_bytes_used:	229738524672
		backup_num_devices:	3

	backup 1:
		backup_tree_root:	1111811768320	gen: 35275	level: 1
		backup_chunk_root:	1111721295872	gen: 33824	level: 1
		backup_extent_root:	1111808262144	gen: 35275	level: 2
		backup_fs_root:		1111808081920	gen: 35275	level: 2
		backup_dev_root:	1112427905024	gen: 33824	level: 1
		backup_csum_root:	1111814733824	gen: 35275	level: 2
		backup_total_bytes:	483183820800
		backup_bytes_used:	229738541056
		backup_num_devices:	3

	backup 2:
		backup_tree_root:	1111816585216	gen: 35276	level: 1
		backup_chunk_root:	1111721295872	gen: 33824	level: 1
		backup_extent_root:	1111815340032	gen: 35276	level: 2
		backup_fs_root:		1111808983040	gen: 35277	level: 2
		backup_dev_root:	1112427905024	gen: 33824	level: 1
		backup_csum_root:	1111818010624	gen: 35276	level: 2
		backup_total_bytes:	483183820800
		backup_bytes_used:	229738541056
		backup_num_devices:	3

	backup 3:
		backup_tree_root:	1111842062336	gen: 35277	level: 1
		backup_chunk_root:	1111721295872	gen: 33824	level: 1
		backup_extent_root:	1111825956864	gen: 35277	level: 2
		backup_fs_root:		1111836409856	gen: 35277	level: 2
		backup_dev_root:	1111842095104	gen: 35277	level: 1
		backup_csum_root:	1111842160640	gen: 35277	level: 2
		backup_total_bytes:	483183820800
		backup_bytes_used:	229738524672
		backup_num_devices:	3





>   btrfs-show-super -a -f /dev/mapper/Data2vg-afs0 (If that is device3 
> and exists)

As I said, the device does no longer exist, because the disk crashed.

>   btrfs-show-super -a -f /dev/mapper/Data3vg-afs0

root@server:~# btrfs-show-super -a -f /dev/mapper/Data3vg-afs0
superblock: bytenr=65536, device=/dev/mapper/Data3vg-afs0
---------------------------------------------------------
csum			0xe3500af0 [match]
bytenr			65536
flags			0x1
magic			_BHRfS_M [match]
fsid			7d4b023a-a1ef-4991-b01d-31e7c4fdfbcf
label			
generation		35278
root			1111813750784
sys_array_size		161
chunk_root_generation	33824
root_level		1
chunk_root		1111721295872
chunk_root_level	1
log_root		0
log_root_transid	0
log_root_level		0
total_bytes		483183820800
bytes_used		229738524672
sectorsize		4096
nodesize		16384
leafsize		16384
stripesize		4096
root_dir		6
num_devices		3
compat_flags		0x0
compat_ro_flags		0x0
incompat_flags		0xe1
			( MIXED_BACKREF |
			  BIG_METADATA |
			  EXTENDED_IREF |
			  RAID56 )
csum_type		0
csum_size		4
cache_generation	35278
uuid_tree_generation	35278
dev_item.uuid		ce22bfec-b82d-42cf-8703-8f1eaa17a1ec
dev_item.fsid		7d4b023a-a1ef-4991-b01d-31e7c4fdfbcf [match]
dev_item.type		0
dev_item.total_bytes	161061273600
dev_item.bytes_used	116534542336
dev_item.io_align	4096
dev_item.io_width	4096
dev_item.sector_size	4096
dev_item.devid		4
dev_item.dev_group	0
dev_item.seek_speed	0
dev_item.bandwidth	0
dev_item.generation	0
sys_chunk_array[2048]:
	item 0 key (FIRST_CHUNK_TREE CHUNK_ITEM 1111721246720)
		chunk length 67108864 owner 2 type SYSTEM|RAID5 num_stripes 3
			stripe 0 devid 2 offset 1048576
			stripe 1 devid 4 offset 1048576
			stripe 2 devid 3 offset 1048576
backup_roots[4]:
	backup 0:
		backup_tree_root:	1111813750784	gen: 35278	level: 1
		backup_chunk_root:	1111721295872	gen: 33824	level: 1
		backup_extent_root:	1111813963776	gen: 35278	level: 2
		backup_fs_root:		1111836409856	gen: 35277	level: 2
		backup_dev_root:	1111814504448	gen: 35278	level: 1
		backup_csum_root:	1111814963200	gen: 35278	level: 2
		backup_total_bytes:	483183820800
		backup_bytes_used:	229738524672
		backup_num_devices:	3

	backup 1:
		backup_tree_root:	1111811768320	gen: 35275	level: 1
		backup_chunk_root:	1111721295872	gen: 33824	level: 1
		backup_extent_root:	1111808262144	gen: 35275	level: 2
		backup_fs_root:		1111808081920	gen: 35275	level: 2
		backup_dev_root:	1112427905024	gen: 33824	level: 1
		backup_csum_root:	1111814733824	gen: 35275	level: 2
		backup_total_bytes:	483183820800
		backup_bytes_used:	229738541056
		backup_num_devices:	3

	backup 2:
		backup_tree_root:	1111816585216	gen: 35276	level: 1
		backup_chunk_root:	1111721295872	gen: 33824	level: 1
		backup_extent_root:	1111815340032	gen: 35276	level: 2
		backup_fs_root:		1111808983040	gen: 35277	level: 2
		backup_dev_root:	1112427905024	gen: 33824	level: 1
		backup_csum_root:	1111818010624	gen: 35276	level: 2
		backup_total_bytes:	483183820800
		backup_bytes_used:	229738541056
		backup_num_devices:	3

	backup 3:
		backup_tree_root:	1111842062336	gen: 35277	level: 1
		backup_chunk_root:	1111721295872	gen: 33824	level: 1
		backup_extent_root:	1111825956864	gen: 35277	level: 2
		backup_fs_root:		1111836409856	gen: 35277	level: 2
		backup_dev_root:	1111842095104	gen: 35277	level: 1
		backup_csum_root:	1111842160640	gen: 35277	level: 2
		backup_total_bytes:	483183820800
		backup_bytes_used:	229738524672
		backup_num_devices:	3


superblock: bytenr=67108864, device=/dev/mapper/Data3vg-afs0
---------------------------------------------------------
csum			0x4331223e [match]
bytenr			67108864
flags			0x1
magic			_BHRfS_M [match]
fsid			7d4b023a-a1ef-4991-b01d-31e7c4fdfbcf
label			
generation		35278
root			1111813750784
sys_array_size		161
chunk_root_generation	33824
root_level		1
chunk_root		1111721295872
chunk_root_level	1
log_root		0
log_root_transid	0
log_root_level		0
total_bytes		483183820800
bytes_used		229738524672
sectorsize		4096
nodesize		16384
leafsize		16384
stripesize		4096
root_dir		6
num_devices		3
compat_flags		0x0
compat_ro_flags		0x0
incompat_flags		0xe1
			( MIXED_BACKREF |
			  BIG_METADATA |
			  EXTENDED_IREF |
			  RAID56 )
csum_type		0
csum_size		4
cache_generation	35278
uuid_tree_generation	35278
dev_item.uuid		ce22bfec-b82d-42cf-8703-8f1eaa17a1ec
dev_item.fsid		7d4b023a-a1ef-4991-b01d-31e7c4fdfbcf [match]
dev_item.type		0
dev_item.total_bytes	161061273600
dev_item.bytes_used	116534542336
dev_item.io_align	4096
dev_item.io_width	4096
dev_item.sector_size	4096
dev_item.devid		4
dev_item.dev_group	0
dev_item.seek_speed	0
dev_item.bandwidth	0
dev_item.generation	0
sys_chunk_array[2048]:
	item 0 key (FIRST_CHUNK_TREE CHUNK_ITEM 1111721246720)
		chunk length 67108864 owner 2 type SYSTEM|RAID5 num_stripes 3
			stripe 0 devid 2 offset 1048576
			stripe 1 devid 4 offset 1048576
			stripe 2 devid 3 offset 1048576
backup_roots[4]:
	backup 0:
		backup_tree_root:	1111813750784	gen: 35278	level: 1
		backup_chunk_root:	1111721295872	gen: 33824	level: 1
		backup_extent_root:	1111813963776	gen: 35278	level: 2
		backup_fs_root:		1111836409856	gen: 35277	level: 2
		backup_dev_root:	1111814504448	gen: 35278	level: 1
		backup_csum_root:	1111814963200	gen: 35278	level: 2
		backup_total_bytes:	483183820800
		backup_bytes_used:	229738524672
		backup_num_devices:	3

	backup 1:
		backup_tree_root:	1111811768320	gen: 35275	level: 1
		backup_chunk_root:	1111721295872	gen: 33824	level: 1
		backup_extent_root:	1111808262144	gen: 35275	level: 2
		backup_fs_root:		1111808081920	gen: 35275	level: 2
		backup_dev_root:	1112427905024	gen: 33824	level: 1
		backup_csum_root:	1111814733824	gen: 35275	level: 2
		backup_total_bytes:	483183820800
		backup_bytes_used:	229738541056
		backup_num_devices:	3

	backup 2:
		backup_tree_root:	1111816585216	gen: 35276	level: 1
		backup_chunk_root:	1111721295872	gen: 33824	level: 1
		backup_extent_root:	1111815340032	gen: 35276	level: 2
		backup_fs_root:		1111808983040	gen: 35277	level: 2
		backup_dev_root:	1112427905024	gen: 33824	level: 1
		backup_csum_root:	1111818010624	gen: 35276	level: 2
		backup_total_bytes:	483183820800
		backup_bytes_used:	229738541056
		backup_num_devices:	3

	backup 3:
		backup_tree_root:	1111842062336	gen: 35277	level: 1
		backup_chunk_root:	1111721295872	gen: 33824	level: 1
		backup_extent_root:	1111825956864	gen: 35277	level: 2
		backup_fs_root:		1111836409856	gen: 35277	level: 2
		backup_dev_root:	1111842095104	gen: 35277	level: 1
		backup_csum_root:	1111842160640	gen: 35277	level: 2
		backup_total_bytes:	483183820800
		backup_bytes_used:	229738524672
		backup_num_devices:	3




> 
> Maybe we can use old super to restore it to a mountable status.
> 
> If you have spare space to backup all the 3 devices, it's recommended to 
> do it, as some repair tips may cause some write into disk, and may even 
> make things worse.
> 

Will do. I have enough space.



Mit freundlichen Grüßen/Kind regards





Felix Koop

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: Help needed to recover a RAID5 btrfs
  2015-05-26 20:15   ` Felix Koop
@ 2015-05-30 12:03     ` Felix Koop
  0 siblings, 0 replies; 6+ messages in thread
From: Felix Koop @ 2015-05-30 12:03 UTC (permalink / raw)
  To: linux-btrfs

Can anyone help me with the next steps? Any chance to recover the data?

Mit freundlichen Grüßen/Kind regards





Felix Koop

> Felix Koop <fdp@fkoop.de> hat am 26. Mai 2015 um 22:15 geschrieben:
> 
> 
> > Qu Wenruo <quwenruo@cn.fujitsu.com> hat am 26. Mai 2015 um 07:56
> > geschrieben:
> > 
> > > Label: none uuid: 7d4b023a-a1ef-4991-b01d-31e7c4fdfbcf
> > >   Total devices 3 FS bytes used 213.96GiB
> > >   devid 2 size 150.00GiB used 108.53GiB path /dev/mapper/Data1vg-afs0
> > >   devid 4 size 150.00GiB used 108.53GiB path /dev/mapper/Data3vg-afs0
> > >   *** Some devices missing
> > The device 3, I guest it's /dev/mapper/data2vg-afs0, does it still 
> > exists in /dev/mapper?
> 
> No, the disk crashed, so that the device does no longer exist.
> 
> > Need some extra info:
> >   btrfs-show-super -a -f /dev/mapper/Data1vg-afs0
> 
> root@server:~# btrfs-show-super -a -f /dev/mapper/Data1vg-afs0
> superblock: bytenr=65536, device=/dev/mapper/Data1vg-afs0
> ---------------------------------------------------------
> csum			0xc33db89c [match]
> bytenr			65536
> flags			0x1
> magic			_BHRfS_M [match]
> fsid			7d4b023a-a1ef-4991-b01d-31e7c4fdfbcf
> label			
> generation		35278
> root			1111813750784
> sys_array_size		161
> chunk_root_generation	33824
> root_level		1
> chunk_root		1111721295872
> chunk_root_level	1
> log_root		0
> log_root_transid	0
> log_root_level		0
> total_bytes		483183820800
> bytes_used		229738524672
> sectorsize		4096
> nodesize		16384
> leafsize		16384
> stripesize		4096
> root_dir		6
> num_devices		3
> compat_flags		0x0
> compat_ro_flags		0x0
> incompat_flags		0xe1
> 			( MIXED_BACKREF |
> 			  BIG_METADATA |
> 			  EXTENDED_IREF |
> 			  RAID56 )
> csum_type		0
> csum_size		4
> cache_generation	35278
> uuid_tree_generation	35278
> dev_item.uuid		5e5332c3-9e02-4b86-a84e-709f6ac4196b
> dev_item.fsid		7d4b023a-a1ef-4991-b01d-31e7c4fdfbcf [match]
> dev_item.type		0
> dev_item.total_bytes	161061273600
> dev_item.bytes_used	116534542336
> dev_item.io_align	4096
> dev_item.io_width	4096
> dev_item.sector_size	4096
> dev_item.devid		2
> dev_item.dev_group	0
> dev_item.seek_speed	0
> dev_item.bandwidth	0
> dev_item.generation	0
> sys_chunk_array[2048]:
> 	item 0 key (FIRST_CHUNK_TREE CHUNK_ITEM 1111721246720)
> 		chunk length 67108864 owner 2 type SYSTEM|RAID5 num_stripes 3
> 			stripe 0 devid 2 offset 1048576
> 			stripe 1 devid 4 offset 1048576
> 			stripe 2 devid 3 offset 1048576
> backup_roots[4]:
> 	backup 0:
> 		backup_tree_root:	1111813750784	gen: 35278	level: 1
> 		backup_chunk_root:	1111721295872	gen: 33824	level: 1
> 		backup_extent_root:	1111813963776	gen: 35278	level: 2
> 		backup_fs_root:		1111836409856	gen: 35277	level: 2
> 		backup_dev_root:	1111814504448	gen: 35278	level: 1
> 		backup_csum_root:	1111814963200	gen: 35278	level: 2
> 		backup_total_bytes:	483183820800
> 		backup_bytes_used:	229738524672
> 		backup_num_devices:	3
> 
> 	backup 1:
> 		backup_tree_root:	1111811768320	gen: 35275	level: 1
> 		backup_chunk_root:	1111721295872	gen: 33824	level: 1
> 		backup_extent_root:	1111808262144	gen: 35275	level: 2
> 		backup_fs_root:		1111808081920	gen: 35275	level: 2
> 		backup_dev_root:	1112427905024	gen: 33824	level: 1
> 		backup_csum_root:	1111814733824	gen: 35275	level: 2
> 		backup_total_bytes:	483183820800
> 		backup_bytes_used:	229738541056
> 		backup_num_devices:	3
> 
> 	backup 2:
> 		backup_tree_root:	1111816585216	gen: 35276	level: 1
> 		backup_chunk_root:	1111721295872	gen: 33824	level: 1
> 		backup_extent_root:	1111815340032	gen: 35276	level: 2
> 		backup_fs_root:		1111808983040	gen: 35277	level: 2
> 		backup_dev_root:	1112427905024	gen: 33824	level: 1
> 		backup_csum_root:	1111818010624	gen: 35276	level: 2
> 		backup_total_bytes:	483183820800
> 		backup_bytes_used:	229738541056
> 		backup_num_devices:	3
> 
> 	backup 3:
> 		backup_tree_root:	1111842062336	gen: 35277	level: 1
> 		backup_chunk_root:	1111721295872	gen: 33824	level: 1
> 		backup_extent_root:	1111825956864	gen: 35277	level: 2
> 		backup_fs_root:		1111836409856	gen: 35277	level: 2
> 		backup_dev_root:	1111842095104	gen: 35277	level: 1
> 		backup_csum_root:	1111842160640	gen: 35277	level: 2
> 		backup_total_bytes:	483183820800
> 		backup_bytes_used:	229738524672
> 		backup_num_devices:	3
> 
> 
> superblock: bytenr=67108864, device=/dev/mapper/Data1vg-afs0
> ---------------------------------------------------------
> csum			0x635c9052 [match]
> bytenr			67108864
> flags			0x1
> magic			_BHRfS_M [match]
> fsid			7d4b023a-a1ef-4991-b01d-31e7c4fdfbcf
> label			
> generation		35278
> root			1111813750784
> sys_array_size		161
> chunk_root_generation	33824
> root_level		1
> chunk_root		1111721295872
> chunk_root_level	1
> log_root		0
> log_root_transid	0
> log_root_level		0
> total_bytes		483183820800
> bytes_used		229738524672
> sectorsize		4096
> nodesize		16384
> leafsize		16384
> stripesize		4096
> root_dir		6
> num_devices		3
> compat_flags		0x0
> compat_ro_flags		0x0
> incompat_flags		0xe1
> 			( MIXED_BACKREF |
> 			  BIG_METADATA |
> 			  EXTENDED_IREF |
> 			  RAID56 )
> csum_type		0
> csum_size		4
> cache_generation	35278
> uuid_tree_generation	35278
> dev_item.uuid		5e5332c3-9e02-4b86-a84e-709f6ac4196b
> dev_item.fsid		7d4b023a-a1ef-4991-b01d-31e7c4fdfbcf [match]
> dev_item.type		0
> dev_item.total_bytes	161061273600
> dev_item.bytes_used	116534542336
> dev_item.io_align	4096
> dev_item.io_width	4096
> dev_item.sector_size	4096
> dev_item.devid		2
> dev_item.dev_group	0
> dev_item.seek_speed	0
> dev_item.bandwidth	0
> dev_item.generation	0
> sys_chunk_array[2048]:
> 	item 0 key (FIRST_CHUNK_TREE CHUNK_ITEM 1111721246720)
> 		chunk length 67108864 owner 2 type SYSTEM|RAID5 num_stripes 3
> 			stripe 0 devid 2 offset 1048576
> 			stripe 1 devid 4 offset 1048576
> 			stripe 2 devid 3 offset 1048576
> backup_roots[4]:
> 	backup 0:
> 		backup_tree_root:	1111813750784	gen: 35278	level: 1
> 		backup_chunk_root:	1111721295872	gen: 33824	level: 1
> 		backup_extent_root:	1111813963776	gen: 35278	level: 2
> 		backup_fs_root:		1111836409856	gen: 35277	level: 2
> 		backup_dev_root:	1111814504448	gen: 35278	level: 1
> 		backup_csum_root:	1111814963200	gen: 35278	level: 2
> 		backup_total_bytes:	483183820800
> 		backup_bytes_used:	229738524672
> 		backup_num_devices:	3
> 
> 	backup 1:
> 		backup_tree_root:	1111811768320	gen: 35275	level: 1
> 		backup_chunk_root:	1111721295872	gen: 33824	level: 1
> 		backup_extent_root:	1111808262144	gen: 35275	level: 2
> 		backup_fs_root:		1111808081920	gen: 35275	level: 2
> 		backup_dev_root:	1112427905024	gen: 33824	level: 1
> 		backup_csum_root:	1111814733824	gen: 35275	level: 2
> 		backup_total_bytes:	483183820800
> 		backup_bytes_used:	229738541056
> 		backup_num_devices:	3
> 
> 	backup 2:
> 		backup_tree_root:	1111816585216	gen: 35276	level: 1
> 		backup_chunk_root:	1111721295872	gen: 33824	level: 1
> 		backup_extent_root:	1111815340032	gen: 35276	level: 2
> 		backup_fs_root:		1111808983040	gen: 35277	level: 2
> 		backup_dev_root:	1112427905024	gen: 33824	level: 1
> 		backup_csum_root:	1111818010624	gen: 35276	level: 2
> 		backup_total_bytes:	483183820800
> 		backup_bytes_used:	229738541056
> 		backup_num_devices:	3
> 
> 	backup 3:
> 		backup_tree_root:	1111842062336	gen: 35277	level: 1
> 		backup_chunk_root:	1111721295872	gen: 33824	level: 1
> 		backup_extent_root:	1111825956864	gen: 35277	level: 2
> 		backup_fs_root:		1111836409856	gen: 35277	level: 2
> 		backup_dev_root:	1111842095104	gen: 35277	level: 1
> 		backup_csum_root:	1111842160640	gen: 35277	level: 2
> 		backup_total_bytes:	483183820800
> 		backup_bytes_used:	229738524672
> 		backup_num_devices:	3
> 
> 
> 
> 
> 
> >   btrfs-show-super -a -f /dev/mapper/Data2vg-afs0 (If that is device3 
> > and exists)
> 
> As I said, the device does no longer exist, because the disk crashed.
> 
> >   btrfs-show-super -a -f /dev/mapper/Data3vg-afs0
> 
> root@server:~# btrfs-show-super -a -f /dev/mapper/Data3vg-afs0
> superblock: bytenr=65536, device=/dev/mapper/Data3vg-afs0
> ---------------------------------------------------------
> csum			0xe3500af0 [match]
> bytenr			65536
> flags			0x1
> magic			_BHRfS_M [match]
> fsid			7d4b023a-a1ef-4991-b01d-31e7c4fdfbcf
> label			
> generation		35278
> root			1111813750784
> sys_array_size		161
> chunk_root_generation	33824
> root_level		1
> chunk_root		1111721295872
> chunk_root_level	1
> log_root		0
> log_root_transid	0
> log_root_level		0
> total_bytes		483183820800
> bytes_used		229738524672
> sectorsize		4096
> nodesize		16384
> leafsize		16384
> stripesize		4096
> root_dir		6
> num_devices		3
> compat_flags		0x0
> compat_ro_flags		0x0
> incompat_flags		0xe1
> 			( MIXED_BACKREF |
> 			  BIG_METADATA |
> 			  EXTENDED_IREF |
> 			  RAID56 )
> csum_type		0
> csum_size		4
> cache_generation	35278
> uuid_tree_generation	35278
> dev_item.uuid		ce22bfec-b82d-42cf-8703-8f1eaa17a1ec
> dev_item.fsid		7d4b023a-a1ef-4991-b01d-31e7c4fdfbcf [match]
> dev_item.type		0
> dev_item.total_bytes	161061273600
> dev_item.bytes_used	116534542336
> dev_item.io_align	4096
> dev_item.io_width	4096
> dev_item.sector_size	4096
> dev_item.devid		4
> dev_item.dev_group	0
> dev_item.seek_speed	0
> dev_item.bandwidth	0
> dev_item.generation	0
> sys_chunk_array[2048]:
> 	item 0 key (FIRST_CHUNK_TREE CHUNK_ITEM 1111721246720)
> 		chunk length 67108864 owner 2 type SYSTEM|RAID5 num_stripes 3
> 			stripe 0 devid 2 offset 1048576
> 			stripe 1 devid 4 offset 1048576
> 			stripe 2 devid 3 offset 1048576
> backup_roots[4]:
> 	backup 0:
> 		backup_tree_root:	1111813750784	gen: 35278	level: 1
> 		backup_chunk_root:	1111721295872	gen: 33824	level: 1
> 		backup_extent_root:	1111813963776	gen: 35278	level: 2
> 		backup_fs_root:		1111836409856	gen: 35277	level: 2
> 		backup_dev_root:	1111814504448	gen: 35278	level: 1
> 		backup_csum_root:	1111814963200	gen: 35278	level: 2
> 		backup_total_bytes:	483183820800
> 		backup_bytes_used:	229738524672
> 		backup_num_devices:	3
> 
> 	backup 1:
> 		backup_tree_root:	1111811768320	gen: 35275	level: 1
> 		backup_chunk_root:	1111721295872	gen: 33824	level: 1
> 		backup_extent_root:	1111808262144	gen: 35275	level: 2
> 		backup_fs_root:		1111808081920	gen: 35275	level: 2
> 		backup_dev_root:	1112427905024	gen: 33824	level: 1
> 		backup_csum_root:	1111814733824	gen: 35275	level: 2
> 		backup_total_bytes:	483183820800
> 		backup_bytes_used:	229738541056
> 		backup_num_devices:	3
> 
> 	backup 2:
> 		backup_tree_root:	1111816585216	gen: 35276	level: 1
> 		backup_chunk_root:	1111721295872	gen: 33824	level: 1
> 		backup_extent_root:	1111815340032	gen: 35276	level: 2
> 		backup_fs_root:		1111808983040	gen: 35277	level: 2
> 		backup_dev_root:	1112427905024	gen: 33824	level: 1
> 		backup_csum_root:	1111818010624	gen: 35276	level: 2
> 		backup_total_bytes:	483183820800
> 		backup_bytes_used:	229738541056
> 		backup_num_devices:	3
> 
> 	backup 3:
> 		backup_tree_root:	1111842062336	gen: 35277	level: 1
> 		backup_chunk_root:	1111721295872	gen: 33824	level: 1
> 		backup_extent_root:	1111825956864	gen: 35277	level: 2
> 		backup_fs_root:		1111836409856	gen: 35277	level: 2
> 		backup_dev_root:	1111842095104	gen: 35277	level: 1
> 		backup_csum_root:	1111842160640	gen: 35277	level: 2
> 		backup_total_bytes:	483183820800
> 		backup_bytes_used:	229738524672
> 		backup_num_devices:	3
> 
> 
> superblock: bytenr=67108864, device=/dev/mapper/Data3vg-afs0
> ---------------------------------------------------------
> csum			0x4331223e [match]
> bytenr			67108864
> flags			0x1
> magic			_BHRfS_M [match]
> fsid			7d4b023a-a1ef-4991-b01d-31e7c4fdfbcf
> label			
> generation		35278
> root			1111813750784
> sys_array_size		161
> chunk_root_generation	33824
> root_level		1
> chunk_root		1111721295872
> chunk_root_level	1
> log_root		0
> log_root_transid	0
> log_root_level		0
> total_bytes		483183820800
> bytes_used		229738524672
> sectorsize		4096
> nodesize		16384
> leafsize		16384
> stripesize		4096
> root_dir		6
> num_devices		3
> compat_flags		0x0
> compat_ro_flags		0x0
> incompat_flags		0xe1
> 			( MIXED_BACKREF |
> 			  BIG_METADATA |
> 			  EXTENDED_IREF |
> 			  RAID56 )
> csum_type		0
> csum_size		4
> cache_generation	35278
> uuid_tree_generation	35278
> dev_item.uuid		ce22bfec-b82d-42cf-8703-8f1eaa17a1ec
> dev_item.fsid		7d4b023a-a1ef-4991-b01d-31e7c4fdfbcf [match]
> dev_item.type		0
> dev_item.total_bytes	161061273600
> dev_item.bytes_used	116534542336
> dev_item.io_align	4096
> dev_item.io_width	4096
> dev_item.sector_size	4096
> dev_item.devid		4
> dev_item.dev_group	0
> dev_item.seek_speed	0
> dev_item.bandwidth	0
> dev_item.generation	0
> sys_chunk_array[2048]:
> 	item 0 key (FIRST_CHUNK_TREE CHUNK_ITEM 1111721246720)
> 		chunk length 67108864 owner 2 type SYSTEM|RAID5 num_stripes 3
> 			stripe 0 devid 2 offset 1048576
> 			stripe 1 devid 4 offset 1048576
> 			stripe 2 devid 3 offset 1048576
> backup_roots[4]:
> 	backup 0:
> 		backup_tree_root:	1111813750784	gen: 35278	level: 1
> 		backup_chunk_root:	1111721295872	gen: 33824	level: 1
> 		backup_extent_root:	1111813963776	gen: 35278	level: 2
> 		backup_fs_root:		1111836409856	gen: 35277	level: 2
> 		backup_dev_root:	1111814504448	gen: 35278	level: 1
> 		backup_csum_root:	1111814963200	gen: 35278	level: 2
> 		backup_total_bytes:	483183820800
> 		backup_bytes_used:	229738524672
> 		backup_num_devices:	3
> 
> 	backup 1:
> 		backup_tree_root:	1111811768320	gen: 35275	level: 1
> 		backup_chunk_root:	1111721295872	gen: 33824	level: 1
> 		backup_extent_root:	1111808262144	gen: 35275	level: 2
> 		backup_fs_root:		1111808081920	gen: 35275	level: 2
> 		backup_dev_root:	1112427905024	gen: 33824	level: 1
> 		backup_csum_root:	1111814733824	gen: 35275	level: 2
> 		backup_total_bytes:	483183820800
> 		backup_bytes_used:	229738541056
> 		backup_num_devices:	3
> 
> 	backup 2:
> 		backup_tree_root:	1111816585216	gen: 35276	level: 1
> 		backup_chunk_root:	1111721295872	gen: 33824	level: 1
> 		backup_extent_root:	1111815340032	gen: 35276	level: 2
> 		backup_fs_root:		1111808983040	gen: 35277	level: 2
> 		backup_dev_root:	1112427905024	gen: 33824	level: 1
> 		backup_csum_root:	1111818010624	gen: 35276	level: 2
> 		backup_total_bytes:	483183820800
> 		backup_bytes_used:	229738541056
> 		backup_num_devices:	3
> 
> 	backup 3:
> 		backup_tree_root:	1111842062336	gen: 35277	level: 1
> 		backup_chunk_root:	1111721295872	gen: 33824	level: 1
> 		backup_extent_root:	1111825956864	gen: 35277	level: 2
> 		backup_fs_root:		1111836409856	gen: 35277	level: 2
> 		backup_dev_root:	1111842095104	gen: 35277	level: 1
> 		backup_csum_root:	1111842160640	gen: 35277	level: 2
> 		backup_total_bytes:	483183820800
> 		backup_bytes_used:	229738524672
> 		backup_num_devices:	3
> 
> 
> 
> 
> > 
> > Maybe we can use old super to restore it to a mountable status.
> > 
> > If you have spare space to backup all the 3 devices, it's recommended to 
> > do it, as some repair tips may cause some write into disk, and may even 
> > make things worse.
> > 
> 
> Will do. I have enough space.
> 
> 
> 
> Mit freundlichen Grüßen/Kind regards
> 
> 
> 
> 
> 
> Felix Koop
> --
> To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: Help needed to recover a RAID5 btrfs
  2015-05-25 16:06 Help needed to recover a RAID5 btrfs Felix Koop
  2015-05-26  5:38 ` Duncan
  2015-05-26  5:56 ` Qu Wenruo
@ 2015-05-26 22:44 ` Omar Sandoval
  2 siblings, 0 replies; 6+ messages in thread
From: Omar Sandoval @ 2015-05-26 22:44 UTC (permalink / raw)
  To: Felix Koop; +Cc: linux-btrfs

On Mon, May 25, 2015 at 06:06:20PM +0200, Felix Koop wrote:
> Hello,
> 
> I have a RAID5 filesystem where one disk has crashed. Now the filesystem is not
> recognized any more. Any help available?
> 
> Here is some info:
> 
> root@server:~# uname -a
> Linux server 4.0.0-1-amd64 #1 SMP Debian 4.0.2-1 (2015-05-11) x86_64 GNU/Linux
> 
> root@server:~# btrfs --version
> btrfs-progs v4.0
> 
> root@server:~# btrfs f sh /dev/Data1vg/afs0
> warning, device 3 is missing
> warning devid 3 not found already
> checksum verify failed on 1111813750784 found 18019A1D wanted FCE227AB
> checksum verify failed on 1111813750784 found 18019A1D wanted FCE227AB
> bytenr mismatch, want=1111813750784, have=65536
> Couldn't read tree root
> Label: none uuid: 7d4b023a-a1ef-4991-b01d-31e7c4fdfbcf
>  Total devices 3 FS bytes used 213.96GiB
>  devid 2 size 150.00GiB used 108.53GiB path /dev/mapper/Data1vg-afs0
>  devid 4 size 150.00GiB used 108.53GiB path /dev/mapper/Data3vg-afs0
>  *** Some devices missing
> 
> btrfs-progs v4.0
> 
> root@server:~# mount -o degraded -r /dev/Data1vg/afs0 /mnt
> mount: wrong fs type, bad option, bad superblock on /dev/mapper/Data1vg-afs0,
>  missing codepage or helper program, or other error
> 
> In some cases useful info is found in syslog – try
>  dmesg | tail or so.
> 
> root@server:~# dmesg | tail
> [104991.996065] BTRFS: open_ctree failed
> [105527.836798] blk_update_request: I/O error, dev fd0, sector 0
> [105527.839477] floppy: error -5 while reading block 0
> [105555.615991] BTRFS info (device dm-52): allowing degraded mounts
> [105555.616000] BTRFS info (device dm-52): disk space caching is enabled
> [105555.665644] BTRFS: bdev (null) errs: wr 38, rd 0, flush 0, corrupt 0, gen 0
> [105556.213570] BTRFS (device dm-52): bad tree block start 14290338419558610620
> 1111828267008
> [105556.216649] BTRFS (device dm-52): bad tree block start 14290338419558610620
> 1111828267008
> [105556.219364] BTRFS: Failed to read block groups: -5
> [105556.236056] BTRFS: open_ctree failed
> 
> 
> If more info is needed, just tell me what I should do. Thanks.
> 

Just a heads up if you manage to mount it, device replace of a missing
device on RAID5/6 will currently oops (see [1]). If you're feeling
really adventurous, you could try my unreviewed patch series here [2],
but that of course depends on the degraded mount succeeding.

1: https://bugzilla.kernel.org/show_bug.cgi?id=96141
2: http://thread.gmane.org/gmane.comp.file-systems.btrfs/45045

-- 
Omar

^ permalink raw reply	[flat|nested] 6+ messages in thread

end of thread, other threads:[~2015-05-30 12:03 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2015-05-25 16:06 Help needed to recover a RAID5 btrfs Felix Koop
2015-05-26  5:38 ` Duncan
2015-05-26  5:56 ` Qu Wenruo
2015-05-26 20:15   ` Felix Koop
2015-05-30 12:03     ` Felix Koop
2015-05-26 22:44 ` Omar Sandoval

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